Low profile reversible three-bar adjustable strap connector



Oct. 29, 1968 D. N. DEWEY ET AL I 3,407,451

LOW PROFILE REVERSIBLE THREE-BAR ADJUSTABLE STRAP CONNECTOR Filed June20, 1966 I0 fie. 4'

INVENTORS DWIGHT N. DEWEY BY JOHN STACHERL' ZM .Z% JWM#: W

' ATTORNEYS United States Patent 3,407,451 LOW PROFILE REVERSIBLETHREE-BAR ADJUSTABLE STRAP CONNECTOR Dwight N. Dewey, West Hartford, andJohn Stacheri, New

Britain, Conn., assignors to The Capeweil Manufacturing Company,Hartford, Conn., a corporation of Connecticut Filed June 20, 1966, Ser.No. 558,909

4 Claims. (Cl. 24-196) ABSTRACT OF THE DISCLOSURE A low profilereversible three-bar quick fit adjustable strap connector is providedwith a rockable gripping bar around which a strap is threaded to providean offset force securing the free end of the strap in adjusted pos1t1on.A channel-shaped tensioner having ends which straddle s de rails of theconnector and includes a bowed leaf spring biasing the tensioner intoengagement with a gripping bar prevents the loosening of the strap whenlittle or no tension is applied to the strap. The channel-shapedtensioner is provided with divergent walls to permit it to t lt slightlyand apply an offset biasing force against the gripping bar to cause itto pinch the strap against an end bar of the connector. The divergentwalls of the tensioner enable it to apply and offset biasing force onthe gripping bar regardless of the reversal of the threading of thestrap around the gripping bar and the bowed spring nested in thetensioner may have a low spring rate to permit the easy threading andadjustment of the strap around the gripping bar while preventinginadvertent loosening.

This invention relates to strap connectors and more particularly to alow profile reversible, quick-fit three-bar adjustable strap connector,having particular utility for adapting or fitting parachute harnesses orthe like to different users.

One of the objects of this present invention is to provide an improvedreversible, adjustable, quick-fit, low profile three-bar strap connectorof the aforedescribed type that will effectively clamp the free end of astrap although the strap is subjected to a relatively great load andwhich, when the load is lessened or removed, will maintain the free endof the strap in the desired adjusted position.

A further object of the present invention is to provide an adjustinglinkage for harness webbing, including a reversible three-bar strapconnector incorporating a novel webbing tensioner that will effectivelysecure the free end of a strap in its adjusted position when the strapis not under heavy load while at the same time permitting the strapportion to be easily and rapidly adjusted. Included in this object isthe provision of a low profile adjusting linkage having minimumsusceptibility to inadvertent adjustment.

Other objects will be in part obvious and in part pointed out more indetail hereinafter.

The invention accordingly consists in the features of construction,combination of elements and arrangement of parts which will beexemplified in the construction hereafter set forth and the scope of theapplication of which will be indicated in the appended claims.

In the drawings:

FIG. 1 is a top plan view of an adjusting linkage for harness webbingembodying the present invention;

FIG. 2 is an exploded view of the webbing tensioner utilized in thepractice of this invention prior to assembly in the strap connectorincorporated in FIG. 1;

FIG. 3 is a fragmentary perspective view of the tensioner of FIG. 1;

FIG. 4 is an enlarged cross-sectional view taken generally along lines44 of FIG. 1 when the straps are under tension; and

FIG. 5 is a cross-sectional view generally similar to that of FIG. 3 buttaken when one of the straps is inverted.

Referring to the drawings in detail, the illustrative strap adjustinglinkage embodying the present invention includes straps 10 and 12, strap10 being fixedly secured to an end bar 13 of a three bar connector 14and strap 12 being adjustably secured to the connector. The strapconnector 14 includes a forged steel frame comprising parallel siderails 16, 18 and transversely disposed integral bars 20, 22 which definea generally rectangular opening 24. A gripping cross bar 26 is supportedon the side rails 16, 18 for sliding and limited rocking movement bymeans of the bifurcated end projections 28 which loosely straddle theside rails 16, 18.

As shown in FIG. 1, the end bar 13 receives the looped end of the strapor webbing 14) which is stitched as indicated at 11 or otherwise securedin permanent fashion to fixedly embrace the end bar 13 within its loop.

The other strap 12 is adapted to be adjustably received by the frame bythreading the free end 12a around the gripping bar 26, between thegripping bar and the transverse end bar 20 and then outwardly of theframe, FIG. 1 showing one method of threading the strap 12 wherein thefree end 12a is initially inserted into the opening 24 from the lowerside thereof. The end bar 20 and gripping bar 26 are provided with acomplementary tongue 30 and groove 52, respectively, which arecooperable to clamp the free end 12a of the strap 12, as shown in FIG.4, when tension is applied to the strap 12 causing the gripping bar 26to slide and limitedly rock relative to the side rails 16, 18.

In many connectors of the aforedescribed type, when the strap 12 is in arelatively relaxed and unclamped state such as when no load is appliedthereto, the free end 12a may move from its adjusted position due tovibrations imposed thereon.

In accordance with this invention, a novel webbing tensioner is providedwhich uniquely obviates the above problem without impairing the normaloperation of the connector 14 or the adjustability of the strap 12.

In the illustrated embodiment, the webbing tensioner 34 comprises agenerally channel-shaped body, formed from sheet material such asstainless steel or the like, which is positioned in the gap 36 formedbetween the transverse bar 22 and the gripping bar 26. The tensioner 34is closely received between side rails 16, 18 and includes first andsecond fiat side walls 38, 40, the ends of which loosely overlie andstraddle the side rails 16, 18 to support the tensioner 34 for slidingand limited rocking movement relative thereto. A bottom wall 42 bridgesthe side walls 33, 40 to hold the tensioner 34 in nestling relationshipwith intermediate transverse bar 22. Since a strap member is notthreaded around transverse bar 22 of the connector, the tensioner 34does not wedge or bind therewith and is free to slide on the sidemembers 16, 18 of the connector 14 under the influence of a very lowbiasing force.

As shown in FIG. 4, the side walls 38, 40 diverge from bottom wall 42and have an included angle of about 10. A bowed leaf spring 44interposed between the tensioner 34 and transverse bar 22 exerts abiasing force lightly urging tensioner 34 (and gripping bar 26) to theright, as viewed in FIG. 4, when little or no tension is applied tostraps 10, 12. As shown in FIG. 4, bottom wall 42 engages free end 12aof strap 12 along a transverse line which is offset or below the planeof the connector 14 Whichpasses through the centers of the transversebars 20, 22 to cause the gripping bar 26 to tilt slightly to increasethe effectiveness of the clamping action on strap 12.

To assemble, the tensioner 34 in which leaf spring 44 is nested isinserted in the gap 36 between transverse bar 22 and gripping bar 26until the end projections of the side wall 40 rest against side rails16, 18 of connector 14. This is accomplished by virtue of a bent up endprojection 38a of wall 38 which allows the insertion of the tensionerbetween side members 16, 18 of the frame. After insertion, endprojection 38a is bent downward into the plane of side wall 38 and thefree end 12a of strap 12 is threaded around gripping bar 26 as shown inFIG. 4. A V-shaped notch 39 having a rounded apex is provided to avoidthe concentration of stresses and fracture as the end 38a is bent out ofand into the plane of side wall 38 for assembly.

With the tensioner 34 assembled in place in the connector 14, the bottomwall 42 of the tensioner will sufficiently force the strap 12 againstthe gripper bar 26 to produce a clamping effect between gripping bar 26and end bar 20, as shown in FIG. 4, which will prevent slippage of thestrap 12 relative to the gripping bar 26 when the strap 12 is not undertension. Although the tensioner 34 will eifectively prevent inadvertentslippage of the strap portion 12a relative to the gripping bar 26, thelow spring rate of the biasing spring 44 will readily permit the strap12 to be manually adjusted.

When the straps 10, 12 are under tension, the gripping bar 26 will rockslightly due to the loose fit between the bifurcated ends 28 of thegripping bar and the side rails 16 and 18 and slide toward the endmember 20 to securely clamp the strap 12 therebetween. By virtue of theuse of a three-bar construction, the strap connector 14 provides a lowprofile or silhouette with the transverse end bar 20 being positionedclosely adjacent to strap 12 and sheltered against accidental contactwhen the connector is used for providing an adjustable parachuteharness. This reduces the possibility of loosening of the harnessthrough an accidental sore-thumb engagement of the connector in use.Moreover, the line of pull between straps and 12 falls along closelyadjacent paths by virtue of the three-bar construction and as a resultthe end bar 13 does not protrude toward the body of the user toconcentrate the impact forces on a small area of the users body underthe shock of parachute opening.

FIG. 5, which is similar to FIG. 4, illustrates the reversibility of thestrap connector. As illustrated in FIG. 5, the strap 12 is threadedaround the gripping bar 26 in the reverse direction from that shown inFIG. 4. In actual practice, this would normally occur when the strap 10sewn to the end bar 13 is twisted a half turn without the knowledge ofthe user. Under such a circumstance, the user would thread the strap 12around the gripping bar 26 in what he believed to be the usual mannerwith the strap 12 near his body and the free end 12a of the strapoverlying the major portion of strap 12. However, since the connector 14is inverted due to the half twist in the strap 10, the user wouldactually be threading the strap 12 around the gripping bar 26 in thereverse direction. Due to the symmetry of the tensioner 34, it is stilleffective to maintain the tension on the strap 12 despite the reversalin the orientation of the strap 12 relative to the gripping bar 26.

From the foregoing, it will be apparent that this invention provides anadjusting linkage for harness webbing incorporating a three-bar strapconnector having a low profile and incorporating a novel webbingtensioner which is effective even though the adjustable strap isthreaded through the connector in the intended or the reverse direction.It is further apparent that the tensioner may utilize a biasing springhaving a low spring rate since the side walls 38, 40 do not engage thestraps or webbing.

As will be apparent to persons skilled in the art, various modificationsand adaptations of the structure above described will become readilyapparent without departure from the spirit and scope of the invention,the scope of which is defined in the appended claims.

We claim:

1. A low profile adjusting linkage for harness webbing and the likeincluding a reversible three-bar strap connector having a pair ofparallel side rails connected by three parallel transverse bars, a firststrap fixedly secured to an end one of said transverse bars and arelatively slidable and rockable gripping bar disposed between the othertwo transverse bars for receiving the free end of a second strapthreaded around said gripping bar and between the gripping bar and theother end bar, a channelshaped tensioner having side walls providing endprojections straddling the side rails of the connector and con-' nectedby a bottom wall, said tensioner side walls diverging from said bottomwall and assembled in nesting relation with the intermediate transversbar of the connector, and a biasing spring interposed between saidintermediate transverse bar and said bottom wall of the tensioner forbiasing the tensioner toward said gripping bar to provide a tensionereffective to maintain the adjustment of the strap members when thestraps are not under tension and regardless of the forward or reversethreading of the adjustable strap member around the gripping member.

2. A linkage as recited in claim 1 wherein the biasing spring is a bowedleaf spring nested between the tensioner and the intermediate transversebar of the connector.

3. A device as recited in claim 1 wherein a V-shaped notch having arounded apex is provided at the inner section of the bottom wall of thetensioner and one of the end projections of a side wall thereof toprevent the fracture thereof when said end projection is bent during theassembly of the tensioner with the connector.

4. A device as recited in claim 1 wherein the included angle between thediverging side walls of the connector is about 10.

References Cited UNITED STATES PATENTS 2,938,254 5/1960 Gaylord 24--l7l3,293,713 12/1966 Gaylord 24-196 BOBBY R. GAY, Primary Examiner.

E. SIMONSEN, Assistant Examiner.

